Maybe look at both scenarios from a crisis perspective.

If you have floating exchange rates (FIAT) and you can inflate your money, you could end up in a hyperinflation: http://en.wikipedia.org/wiki/Hyperinflation
If you follow a strict gold-backed standard you may end up in a deflationary spiral: http://en.wikipedia.org/wiki/Debt_deflation

If you pretend you have a gold-standard but pursue an inflationatory policy, things also get interesting http://en.wikipedia.org/wiki/Bretton_woods_system

And with respect to buy silver, that is actually not that far off
"Today, there is no government agency, that would pay for the payment promises of Alexander the Great, Julius Caesar, Louis XIV, Peter the Great, Napoleon or Hitler. They were powerful men in their time, but no bank will cash their checks today. If you take a gold bar, however, that once lay in their treasuries, you will receive its equivalent value anywhere in the world. The durability and universality of gold gives it a money-like authority, that no other money has." (William Rees-Mogg – former chief editor of the London Times)

Power looks alright for both cards.

Maybe someone else can comment on the board. Sticking the 2nd card into the PCIe x1 slot may degrade the mining performance.

Something to consider...
Maybe you want to expand the set-up later on.
Look for sale items, maybe you can get a decent 750W power supply later on that can supply more cards.
I would personally go for a board that has more PCIex16 slots. Then you can always add more later on and do not need to scrap your entire rig, when you get tired of it.

I read your post. I would come from the other end. Instead of making centralized somehow P2P, build a simple distributed system that acts as a market.

For price-discovery you could just use a simple call-market: http://www.investopedia.com/terms/c/callmarket.asp#axzz1Q4BdJydP
and slowly grow that into a continuous market (NASDAQ-like bid-ask matching). I did some research with distributed pub-sub frameworks and DHTs in the past. I find that feasible.

Regulation is going to be a pain. But as long as you keep it simple, you won't have to worry about it. For example if you make all bids final for a period, you may avoid front-running. If you do not allow derivatives being part of the market itself, you also save yourself a lot of trouble there.

Think like the old Mercedes-Diesel Engineers (like the guys pre-1990s not the guys who engineer the junk today): "Everything that is excluded from the design, cannot break."

I would love to see or even join some research which techniques may be useful for bitcoin. However, I have the feeling that bitcoin including bitcoin exchanges in their distributed nature are a different phenomenon than Forex.

Did you already run some stuff on bitcoin data?

Just out of curiosity, what makes you believe that those methods would work on the current bitcoin setup?

I think fundamental techniques may actually at the time be a more promising avenue. Since the market is not centralized and you do not have accurate volume numbers, the assumption of emergent trends that is baked into these technical indicators may not be valid.

PS: I do not mean to criticize your post. I'm just joining Bitcoin from the other end of the investment spectrum, the (physical!) precious metals pit; people who still believe that Forex trading is actually a fluke that resulted from the failure of the Bretton-Woods System in 1971: http://en.wikipedia.org/wiki/Bretton_Woods_system.

It's fundamental economics, specifically Greshams Law: http://en.wikipedia.org/wiki/Gresham's_law

CITE: "This law applies specifically when there are two forms of commodity money in circulation which are required by legal-tender laws to be accepted as having similar face values for economic transactions. The artificially overvalued money tends to drive an artificially undervalued money out of circulation and is a consequence of price control."

If people have to choose among different types of money they spend the "artificially" overvalued money and hoard "the real money". And looking at bitcoins, they actually have several advantages over paper money.

Hi Arashd,
hey, same here. I just ordered my list of goodies. I went for 2x6950s (and still reserve the option to buy more later) instead of 6990s because the cost-reward factor was still to high. You can get 6950s in my area for 250$, but the 6990s are way up in the 700$-range.

What you need is a board that can host those graphics cards side-by-side. They usually take two slots, so the PCIe slots should be spaced further apart.

This board did it for me: http://www.gigabyte.com/products/product-page.aspx?pid=3880#ov
You can stick in 4 PCIe x16 graphics cards side-by-side. See the nice little picture in the promo.

Since most of the Bitcoin operations do use the GPU, I bought an AMD Phenom II x2 250, which was on sale. I also stuck in a 4GB DDR3 module.

What you need next is at least a 750W power supply that can power your 3 cards (or in my case later on 4). This one can do and was on sale at my retailer: http://www.ocztechnology.com/ocz-750w-fatal1ty-series-power-supply.html

For the case I recycled an old server case that formerly hosted an old Dual-Xeon server.

I hope it helps. If I were you I wouldn't throw my life savings into the 6690s, at the current bitcoin mining difficulty it'll take quite some time until you get your return on it, even with 2Ghash/sec.

Here are some numbers with $/Mhash figures and more ideas about rigs: https://en.bitcoin.it/wiki/Mining_rig

Ready to start making Bitcoin exchanges more secure.

I just found out about Bitcoin a couple weeks ago and now they are having a depression because of hacked exchanges.

Anyone else thinking of building a full P2P Bitcoin exchange?

I did some work with with Distributed Hash Tables and distributed publish-subscribe frameworks in the past. This would be a potential resilient infrastructure to build an exchange.

Lea